Heavy Metals Concentrations in Roadside Dust of Different Traffic Density

Abstract

This study investigated effect of vehicular emission on heavy metals levels along selected roads of different traffic densities in Abeokuta, Nigeria. Roadside dusts were randomly collected from both sides of the roads and digested. The digested sample solutions were then analyzed using Atomic Absorption Spectrophotometer (AAS) for the determination of Pb, Cd, Zn and Ni concentrations. Replicate analyses were carried out on each sample. Data were subjected to descriptive statistics and analysis of variance. Means were separated using Duncan’s Multiple Range (DMR) test. Pearson’s correlation coefficient was used to determine the relationship between the metals. The mean concentrations of the metals were found to follow the decreasing order: Pb > Zn > Ni > Cd. The road with significantly (P < 0.05) higher traffic density had significantly (P < 0.05) higher levels of the metals investigated. There was significant (p < 0.05) positive correlation between the metals.

Key words: Heavy metals, Roadside, Dust, Traffic density